In various fields of so-called seamless positioning, motion sensing, posture control and the like, the utilization of sensors has attracted attention. As sensors, an acceleration sensor, a gyro sensor, a pressure sensor, a geomagnetic sensor and the like are widely known. A technique for calculating the positions of mobile bodies (such as, for example, a bicycle, an automobile, an electric train, a ship, and an airplane) by performing inertial navigation calculation using measurement results of sensors has also been devised.
In inertial navigation calculation, there is a problem that the accuracy of position calculation drops due to various error components which may be included in measurement results of a sensor, and thus various techniques for improving the accuracy of position calculation have been devised. For example, JP-A-2012-194175 discloses a technique in which, with a mobile body such as four-wheeled automobile as a target, the installation posture of a sensor with respect to the mobile body is determined, and the position or velocity of the mobile body is calculated.